Question

Index of refraction of glass of angle incidence zero and medium is water

Answer 1

Now

Angle of incident is zero

It means that the angle between normal and incident ray equal zero

If a ray fll perpendicular on the refraction surface it goes into a second medium without deviation 

this is because case

i=0°

From smell's law

$n=\frac{sini}{sinr}$

$sinr=\frac{sini}{n}=0;r=0°$

$i=r=0°$

it means no refraction glass to the water